Windows Forms

How to Raise event before and after loading data to datagridview when virtual mode on

20-Jul-15 9:45

Tridip Bhattacharjee wrote:
one thing is not clear to me which function is getting called first when user
scroll datagridview.

You should read more of what is one MSDN, as it explains the topic quite well. The "ValueNeeded" event is called for each cell that needs painting, regardless of what causes the paint; whether that is a scroll, or maximizing the form. If the grid needs values, that event is fired.

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If you can't read my code, try converting it here[^]

Tridip Bhattacharjee18-Jul-15 6:47

Tridip Bhattacharjee

18-Jul-15 6:47

My datagridview virtual mode is turned on.so i have to populate grid this way

private void dataGridView1_CellValueNeeded(object sender,DataGridViewCellValueEventArgs e)
{
e.Value = memoryCache.RetrieveElement(e.RowIndex, e.ColumnIndex);
}

from these thread

http://stackoverflow.com/questions/13856869/notify-when-event-from-another-class-is-triggered
http://stackoverflow.com/questions/4378339/raise-an-event-of-a-class-from-a-different-class-in-c-sharp

i got the logic how to raise event to calling environment.

i am in confusion from where to raise event in my code. apologized that i could not submit my full code but here i am mentioning a url where i post my full working code. please have a look and guide me how to raise event from my code.

so this is the url where i post my full working code

http://stackoverflow.com/questions/31458197/
how-to-sort-datagridview-data-when-virtual-mode-enable/31475803#31475803

My Objective

i want to raise a event when data load will start and again want to raise another event after populating all rows of the grid.

my Event handler code would look like

public void BeginDataLoad(object sender, EventArgs e)
{
//Do something here
}

public void EndDataLoad(object sender, EventArgs e)
{
//Do something here
}

looking for help with code sample. thanks

tbhattacharjee

Re: How to Raise event before and after loading data to datagridview when virtual mode on

Eddy Vluggen20-Jul-15 9:42

Use of Unicode characters -> Syntax.

20-Jul-15 9:42

Your loaddata-event is when the memorycache is being built. The enddata when it is done.

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Mateo Hernández17-Jul-15 3:30

Re: Use of Unicode characters -> Syntax.

17-Jul-15 3:30

HI, guys!
I have a function in my application that searches for horizontal tabs in a text file. So far, I've been using a String^ variable named "Glo::m_tab" initialized as L" ". Works fine.

But what if I want to look for a black star, or a form feed or any other control character within the file?. How do I work the U+0009 code for HT into my function?. I've found no examples.

THANK YOU!!

Richard MacCutchan17-Jul-15 3:33

Richard MacCutchan

17-Jul-15 3:33

Please review the documentation[^].

Re: Use of Unicode characters -> Syntax.

Mateo Hernández18-Jul-15 3:37

18-Jul-15 3:37

THANK YOU! I will.

Windows Form Shown

Mateo Hernández12-Jul-15 12:58

12-Jul-15 12:58

Hi, guys!.
I need one of my forms to do something immediately after the form itself and all the controls are shown (all initialized), but before the user even clicks on anything. THANK YOU!

P.S.: I'm not an expert. It's written in C++ .NET using Visual Studio 2010. I tried the Form_Shown event, but it didn't work. Thanks again.

erwinliong12-Jul-15 14:55

erwinliong

12-Jul-15 14:55

What you need is Windows.Form.Load Event override. See following link for example

https://msdn.microsoft.com/en-us/library/system.windows.forms.form.load(v=vs.110).aspx[^]

Mateo Hernández12-Jul-15 20:45

12-Jul-15 20:45

Thanks for the suggestion. I'll try it.

Mateo Hernández12-Jul-15 23:11

12-Jul-15 23:11

Hi!
As you suggested, I tried the example in

https://msdn.microsoft.com/en-us/library/system.windows.forms.form.load%28v=vs.100%29.aspx[^]

Had to change the code a bit, but managed to get it working and added a Form1_Shown event as well. Two things:
1) IMHO, I think that's what I need instead of a Form1_Load event, because I want to add something after the form has loaded and displayed all the controls with their initial values.
2) I have a bigger question now: What's the practical difference between the load event and the constructor code that I can write at the beginning of the form, right after the InitializeComponent() part?
Can you help me? THANK YOU, again!

Sascha Lefèvre13-Jul-15 4:20

Sascha Lefèvre

13-Jul-15 4:20

Mateo Hernández wrote:
What's the practical difference between the load event and the constructor code that I can write at the beginning of the form

Please see here:
http://stackoverflow.com/questions/2521322/what-setup-code-should-go-in-form-constructors-versus-form-load-event[^]
and here:
http://stackoverflow.com/questions/3070163/order-of-events-form-load-form-shown-and-form-activated-in-windows-forms[^]

If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

Mateo Hernández17-Jul-15 3:14

Folder Permissions - Urgent Help Please

17-Jul-15 3:14

Thank you!!

Seuss13-May-15 3:09

Seuss

13-May-15 3:09

Hi
I am in need of help please as I am not familiar with the folder permissions stuff.

Everyone has access to a particular folder where the files are held.

Q1. The folder permissons have 'EVERYONE' set to tick on everything

Full control
Modify
Read & Execute
List Folder contents
Read

There is also [company name]/Administrators - they have the same settings as above.
There is another group for everyone [CompanyName]/[CompanyName]

How can we prevent access to this folder for everyone?
The problem is in the VB.Net application, there are some forms that creates a file in that folder and 'everyone' who logs into this application are allowed to generate a file
that is written to this folder BUT we don't want them having access to the folder to see all the files.

The software (VB.Net) actually generates files by a logged in user but they shouldn't be able to access the folder when they go to the My Computer->Network->Folder.
We need to make sure it is creating the files and can view documents within the software only.

What can be done on the folder for Q1?

Would appreciate the help

modified 13-May-15 10:34am.

Re: Folder Permissions - Urgent Help Please

Dave Kreskowiak25-May-15 3:57

Dave Kreskowiak

25-May-15 3:57

Considering a Windows Forms application runs AS THE USER THAT LAUNCHES IT, so your security isn't really going to work. At BEST, what you're going to be able to do is prevent users from casually looking in the folder to see, well, nothing. The user wouldn't be able to see the files in the folder. All you have to do is turn off the "List folder contents" permission.

I said "casually" for a reason. Users and/or administrators will still be able turn that permission back on and easily see the files in the folder.

You basically have no recourse to do what you want. In order for the application to work on the files it needs to it needs a certain minimum set of permissions. That means that the users running the application need those permissions. You set permissions on users and groups of users, not applications.

Oh, and nothing in a forum environment is "urgent". Everyone here volunteers whatever time they have to answering questions on forums.

A guide to posting questions on CodeProject

Click this: Asking questions is a skill.
Seriously, do it.

Dave Kreskowiak

Re: Folder Permissions - Urgent Help Please

Nitzan Levi22-Aug-15 19:50

Nitzan Levi

22-Aug-15 19:50

you need to change the user that your application is running under. see samples:

User Impersonation in .NET[^]

http://stackoverflow.com/questions/1168571/run-code-as-a-different-user-c[^]

http://stackoverflow.com/questions/125341/how-do-you-do-impersonation-in-net/7250145#7250145[^]

Accordion in windows Forms

sudevsu24-Apr-15 5:25

24-Apr-15 5:25

Could someone help in understanding with examples of multiple controls in a Panel which is in an Table layout and should behave like web Accordion? I have gone through the websites and other tutorials but none of those examples have real time scenarios. So it is very hard to find the exact procedure of accordion will act in windows forms with multiple controls like textbox, combo box, checked list box, button etc. I would like to have one such article with real time Examples of Code snippets from SA because this concept has not been explained properly anywhere in google with snippets and examples

Your help is much appreciated.
Thanks
Happy Coding!

Richard MacCutchan24-Apr-15 7:01

Richard MacCutchan

24-Apr-15 7:01

Please read http://www.codeproject.com/Messages/3137519/Forum-Guidelines-PLEASE-READ.aspx[^].

sudevsu24-Apr-15 7:29

24-Apr-15 7:29

Oops. I am sorry. I don't want to help me in writing an article. I actually wanted an article/ tutorial to understand accordion in windows forms. I am working on windows forms and I wanted to do something like in Web Accordions. That's the only intension.

Your help is much appreciated.
Thanks
Happy Coding!

Eddy Vluggen24-Apr-15 7:28

24-Apr-15 7:28

What do you mean by "real time"? Unsure | :~

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

sudevsu24-Apr-15 7:32

24-Apr-15 7:32

Meaning I worked on one such form and I tried to create my own code for accordion. But my form has only label as control. If I add more controls, I do not know how to proceed for accordion. Real time meaning: which has most used the controls in the form like combo box, listbox, button etc

Your help is much appreciated.
Thanks
Happy Coding!

Eddy Vluggen24-Apr-15 7:38

24-Apr-15 7:38

I'm sorry, but I'm having trouble understanding what you are trying to do, or where you are stuck.

Perhaps some code would help; or a picture Smile | :)

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

sudevsu24-Apr-15 7:59

24-Apr-15 7:59

OK let me put this again Clear. You must be knowing for Accordion in Web applications work.
I want a similar one in windows. I already did try. But If my panel has any other controls other than Label, it doesn't work. Could not figure it out how to achieve this with all the controls in the panel.
Here is the code that will act labels click as accordion

Private Sub ButtonClick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label2.Click, Label3.Click, Label5.Click
    'find out which label was clicked
    Dim lbl As Label = CType(sender, Label)
    'find the panel containing the label
    Dim pnl As Panel = lbl.Parent

    For Each p As Panel In TableLayoutPanel1.Controls
      Dim l As Label = CType(p.Controls(0), Label)
      If p.Equals(pnl) Then
        'expand or collapse the panel
        If p.Height = 150 Then
          p.Height = 25
          l.ForeColor = Color.Black
        Else
          p.Height = 150
          l.ForeColor = Color.Black
        End If

      Else
        p.Height = 25
        l.ForeColor = Color.Black
        l.Image = My.Resources.arrow
      End If
    Next
  End Sub

Your help is much appreciated.
Thanks
Happy Coding!